CN103713294A

CN103713294A - All band gnss receiver

Info

Publication number: CN103713294A
Application number: CN201310025062.3A
Authority: CN
Inventors: 王航; 李涛; 张丙雷; 莫世雄
Original assignee: Aviacomm Inc
Current assignee: Nanjing Qixin Semiconductor Co.,Ltd.
Priority date: 2012-10-04
Filing date: 2013-01-11
Publication date: 2014-04-09
Anticipated expiration: 2033-01-11
Also published as: US9170336B2; CN103713294B; US20160018529A1; US20140098839A1

Abstract

One embodiment of the present invention provides a signal-recording system. During operation, the system receives a plurality of radio frequency (RF) signals, separates the RF signals to obtain a first group of RF signals in a first RF band and a second group of RF signals in a second RF band, and simultaneously down-converts the first group of RF signals to a first group of low intermediate-frequency (low-IF) signals in a first IF band and the second group of RF signals to a second group of low-IF signals in a second IF band. The system further converts the first group of low-IF signals and the second group of low-IF signals to the digital domain, and simultaneously processes all of the converted low-IF signals.

Description

Whole frequency band GNSS receiver

Technical field

Present disclosure mainly relates to a kind of satellite signal receiving system.More specifically, present disclosure relates to and a kind ofly can receive from all four GLONASS (Global Navigation Satellite System) (GNSS) system of signal.

Background technology

In recent years, portable satellite signal receiving equipment prevailing caused the various aspects expansion that the use of satellite navigation is lived from military field to citizen.For example nowadays most smart phones are equipped with and realize built-in global positioning system (GPS) receiver that real time position is followed the tracks of and direction instructs.

Have at present four of Global coverage GLONASS (Global Navigation Satellite System) (GNSS) can be provided, these systems comprise the system (the compass navigational system of China and the Galileo positioning system of European Union) of two full operation systems (the NAVSTAR GPS of the U.S. and Russian Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS)) and two Part Developments.

Summary of the invention

One embodiment of the present of invention provide a kind of signal recording system.During operation, this system receives a plurality of radio frequencies (RF) signal, separated RF signal to obtain first group of RF signal in a RF frequency band and second group of RF signal in the 2nd RF frequency band and first group of RF signal down to be converted to first group of Low Medium Frequency (low IF) signal in an IF frequency band and second group of RF signal down is converted to second group low IF signal in the 2nd IF frequency band simultaneously.This system is also converted to first group low IF signal and second group low IF signal numeric field and processes all low IF signals through conversion simultaneously.

In the variation about this embodiment, process all low IF signals through conversion simultaneously and comprise the low IF signal of selecting corresponding low IF signal and treatment of selected to select based on IF carrier frequency.

In the variation about this embodiment, process all low IF signals through conversion simultaneously and comprise digital signal processor (DSP), this DSP comprises a plurality of processing units.

In the variation about this embodiment, at the frequency difference between a RF frequency band and the 2nd RF frequency band, be greater than the frequency difference between an IF frequency band and the 2nd IF frequency band.

In another variation, the frequency difference between a RF frequency band and the 2nd RF frequency band is at least 200MHz.

In the variation about this embodiment, RF signal comprises the satellite-signal from a plurality of GLONASS (Global Navigation Satellite System).

In the variation about this embodiment, the satellite-signal of this system based on from a plurality of GLONASS (Global Navigation Satellite System) generates the location output of combination.

In the variation about this embodiment, a plurality of GLONASS (Global Navigation Satellite System) comprise: GPS (GPS); Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS); Compass navigational system; And Galileo positioning system.

In the variation about this embodiment, the bandwidth of the RF signal of reception surpasses 400MHz.

Accompanying drawing explanation

Fig. 1 has presented the figure that illustrates two RF frequency band that GNSS signal takies.

Fig. 2 has presented and has illustrated the figure of the framework of example double frequency-band satellite signal receiver according to an embodiment of the invention.

Fig. 3 has presented and has illustrated according to an embodiment of the invention two through the figure of intermediate frequency (IF) frequency bands of frequency reducing conversion.

Fig. 4 has presented and has illustrated the figure of the framework of example multiband digital signal processor (DSP) according to an embodiment of the invention.

Fig. 5 has presented the figure that illustrates the instantiation procedure that receives according to an embodiment of the invention multi-band RF signal.

Embodiment

Present following description so that any person skilled in the art can realize and use the present invention, and provide following description in the background of concrete application and requirement thereof.Will be easily clear by those skilled in the art to the various modifications of disclosed embodiment, and the General Principle limiting here can be applied to other embodiment and application and not depart from Spirit Essence of the present invention and scope.Therefore, the invention is not restricted to illustrated embodiment but will be endowed the widest scope consistent with principle disclosed herein and feature.

general introduction

Some embodiments of the present invention provide a kind of double frequency-band satellite signal receiver that can receive the satellite-signal that takies two frequency band.Double frequency-band satellite signal receiver comprises broad-band antenna; Separately for two groups of wave filter/down converters of a frequency band; Analog to digital converter (ADC); And many baseband digital signals processor (DSP).More specifically, every group of wave filter/down converter comprise bandpass filter (BPF), one or more low noise amplifier (LNA) and by satellite-signal from RF frequency band conversion to Low Medium Frequency the mixer of (IF).After frequency reducing conversion, before the many base band DSP to processing all four GNSS signals sends, combination and AD conversion are from the satellite-signal of two RF frequency bands.

gNSS receiver

Often to the popular application of having ordered about the many location sensitive of exploitation of the portable satellite signal receiver building in various types of smart mobile phones, such as navigation, the social media application that nearest point of interest location, position are known, exercise etc.Most usable satellite signal receivers are gps receivers, this means that they receive signal from the gps satellite of the U.S..Due to GPS the mid-90 in 20th century become the whole world available, so it has been the maximum satellite navigation system of utilization in the world.Yet have locating information also can be provided comprise GLONASS, compass and Galilean other GLONASS (Global Navigation Satellite System).Hope utilizes all available global positioning systems to realize best positioning result by receive signal from all systems simultaneously, and this positioning result comprises improvement covering and the faster response time in urban canyons.Can from the current available system of a plurality of GNSS systems reception signals, often depend on separately for receive a plurality of individual receivers of signal from a system.Use individual receivers not only increase manufacturing cost and overall system complicacy but also may cause the power consumption of increase and the system reliability of minimizing.In order to address this problem, embodiments of the invention provide a kind of and use single receiver with the satellite signal receiving system from all GNSS system picked up signal.

All satellites in gps system are in 1575.42MHz (so-called L1 signal) and this identical two frequencies broadcast of 1227.60MHz (so-called L2 signal).GLONASS satellite is in 1602MHz or 1246MHz broadcast.Compass satellite is designed in 1561.098MHz, 1589.742MHz, 1207.14MHz and 1268.52MHz broadcast.On the other hand, Galileo takies the frequency band between 1164-1215MHz, 1260-1300MHz and 1559-1592MHz.Generally, satellite-signal from all GNSS systems takies two frequency band, and one of them extends to 1298.75MHz (being called in this disclosure FSpan_1) and another extends to 1610MHz (being called in this disclosure FSpan_2) from 1559.052MHz from 1176.45MHz.Fig. 1 has presented the figure that illustrates two RF frequency band that GNSS signal occupies.Note, these two frequency bands take the frequency range that is greater than 400MHz, and spacing between two frequency bands is greater than 200MHz.

In order to receive all GNSS signals, receiver may be from FSpan_1 frequency band and the two reception signal of FSpan_2 frequency band.A kind of simple directly solution be use can range of receiving from FSpan_1 frequency band edge to the broadband reception device of the signal on the upper edge of FSpan_2 frequency band.Yet, this means any signal being also received in two spacing between frequency band, this may cause the interference to received satellite-signal.In addition, all parts in such solution requirement receiver receive the bandwidth that is greater than 400MHz, and this may be challenge for RF deviser.

Fig. 2 has presented and has illustrated the figure of the framework of example double frequency-band satellite signal receiver according to an embodiment of the invention.In Fig. 2, double frequency-band satellite signal receiver 200 comprises broad-band antenna 202, FSpan_1 RX path 204, FSpan_2 RX path 206, combiner 208, analog to digital converter (ADC) 210 and many baseband digital signals processor (DSP) 212.

During operation, broad-band antenna 202 is from all four GNSS system receiving satellite signals.The signal receiving is sent to two RX path, and the filtering then of each RX path, amplification and frequency reducing conversion are from the RF satellite-signal of the reception of respective frequencies frequency band.More specifically, signal to intermediate frequency (IF) in FSpan_1 RX path 204 filtering, amplification and frequency reducing conversion FSpan_1 frequency band; And signal in 206 filtering of FSpan_2 RX path, amplification and frequency reducing conversion FSpan_2 frequency band is to different intermediate frequencies (IF).Note, carefully select these two IF with prevent between the signal in two original frequency band, any overlapping in frequency domain.

FSpan_1 RX path 204 comprises bandpass filter (BPF) 214, RF low noise amplifier (LNA) 216, mixer 218, BPF220 and IF amplifier 222.Select the RF satellite-signal that the first filtering of BPF214 of the signal in FSpan_1RF frequency band receives by antenna 202 and refuse other out-of-band-signal, such as the signal from FSpan_2 frequency band.Then the signal of filtering was amplified by RF LNA216 before being converted to low IF signal by mixer 218 frequency reducings.Carefully select IF to be kept away from DC preventing from disturbing, such as flicker noise to guarantee the FSpan_1 frequency band of frequency reducing conversion.Attention is for the object of simplifying, not shown local oscillator in Fig. 2, and these local oscillators provide the sine wave mixing with RF signal.Thereby BPF220 filtering summation frequency signal and other non-required signal only leave required low IF signal.IF amplifier 222 amplifies IF signal.In one embodiment, IF amplifier 222 also carrying out automatic gain control (AGC) to realize optimum amplification effect.

Parts in FSpan_2 RX path 206 are selected signal and mixer 226 in FSpan_2 frequency band except wave filter 224 frequency reducing of FSpan_2 band signal are converted to different I F frequency similar to the parts in FSpan_1 RX path 204.Note, carefully select IF frequency in FSpan_2 RX path 206 to guarantee between two IF frequency bands without overlapping.Combiner 208 combinations are from the signal of two IF frequency bands.In one embodiment, combiner 208 is simple totalizers.Fig. 3 has presented the figure of the IF frequency band that illustrates according to an embodiment of the invention two frequency reducing conversions.

As shown in Figure 3, FSpan_1 ' frequency band is the IF frequency band for the frequency reducing conversion of original FSpan_1 frequency band, and FSpan_2 ' frequency band is the IF frequency band for the frequency reducing conversion of original FSpan_2 frequency band.Compare with frequency spectrum shown in Fig. 1, the signal in IF frequency band has much lower carrier frequency, and compares much smaller in the spacing between two IF frequency bands with the spacing between two original RF frequency bands.In one embodiment, the bandwidth of all IF signals is about 200MHz, and shown in this frequency ratio Fig. 1,400MHz bandwidth is much smaller.

ADC210 is converted to numeric field by the composite signal from two IF frequency bands.In one embodiment, ADC210 is 3 ADC with 400MHz sampling rate.Also likely use the more ADC of low resolution, such as 1 ADC or 2 ADC.Yet 3 ADC strengthen system reliability.Note, the sampling rate of ADC210 depends on the bandwidth of IF signal.In example shown in Fig. 3, IF signal has the bandwidth of about 200MHz, this means at least sampling rate of 400MHz.

Then to many base band DSP212 send comprise from the digitized signal of the signal of all four GNSS systems for the treatment of.Many base band DSP212 can process signal or the signal in a plurality of carrier frequencies of a plurality of channels simultaneously.Fig. 4 has presented and has illustrated the figure of the framework of example multiband DSP according to an embodiment of the invention.

In Fig. 4, many base band DSP400 comprises bank of filters 402 and processor group 404.Bank of filters 402 comprises a plurality of digital BPF, such as BPF406, BPF408, BPF410 and BPF412.Processor group 404 comprises a plurality of processors, such as processor 414, processor 416, processor 418 and processor 420.During operation, each signal that receives digitizing IF signal and be chosen in corresponding channel since ADC of digital BPF406-412.For example, the centre frequency of BPF406 is tuned to GPS L1 frequency (1575.42MHz) to select GPS L1 signal, and the centre frequency of BPF408 can be tuned to 1602MHz to select GLONASS signal.Then to processor, send output through filtering for further processing, such as digital frequency reducing conversion, decoding and location Calculation.In one embodiment, processor can cooperatively interact and generate output with the signal based on from all four satellite systems.

Fig. 5 has presented the figure that illustrates the instantiation procedure that receives according to an embodiment of the invention multi-band RF signal.During operation, broad-band antenna receives multi-band RF signal (operation 502).In one embodiment, RF signal occupies wherein the independent RF frequency band of two of frequency difference.In another embodiment, frequency difference is at least 200MHz.Then the frequency band that the RF signal based on receiving belongs to is separated their (operations 504) spatially.In one embodiment, the spatially separated BPF that has different passbands is used for realizing this goal.

Subsequently the RF signal down of each frequency band is converted to corresponding IF signal (operation 506).Carefully select IF frequency to guarantee having frequency overlapping between IF frequency band.In one embodiment, take and remain on two spacing between adjacent IF frequency band and select IF frequency as minimum mode.After frequency reducing conversion, combine all IF frequency bands (operation 508), and at the single ADC of suitably sampling rate operation, the IF signal of combination is converted to numeric field (operation 510).To many base band DSP, send digital signal, the carrier frequency of this many base band DSP (use digital filter) based on each level signal, to its filtering, then processed each level signal (operation 512).Here notice that carrier frequency is IF carrier wave rather than original RF carrier wave, and between RF carrier frequency and IF carrier frequency, have man-to-man corresponding.In one embodiment, can combine digital change so that each IF signal is converted to base band.System also produces the output (operation 514) of combination based on all signals.For example, if multi-band signal is the satellite-signal from all four GNSS systems, the output of combination can be the geographic position based on calculating from the information of all GNSS systematic collections.

Generally speaking, from depend on a plurality of receivers to compare from the traditional scheme of different GNSS system receiving satellite signals, in some embodiments of the invention, signal from different GNSS systems is received by single receiver, and this receiver comprises separately two RX path for characteristic frequency frequency band.Notice that each frequency band comprises the signal from different GNSS systems, each GNSS system is on different carrier frequencies.In addition, two RX path are shared a plurality of common elements, such as antenna, ADC and DSP, therefore significantly reduce power consumption and system complexity.

Note, framework shown in Fig. 2 and Fig. 4 is not only for limiting the scope of the disclosure for example.For example, in Fig. 2, frequency mixer is used for RF signal down to be converted to IF.In practice, other frequency reducing conversion plan, is also possible such as quadrature frequency reducing conversion.In addition, Fig. 4 illustrates the processor group comprising for the treatment of a plurality of processors of digitizing satellite-signal.In practice, processor number can change.In certain embodiments, single powerful processors is used for processing the signal from all GNSS systems.In certain embodiments, for the signal from particular satellite system distributes application specific processor.

Also notice that present disclosure is used satellite-signal as an example.In practice, embodiments of the invention are disclosed single and authorize and also can receive the multi-band signal of other type, and the multi-band signal of these other types includes but not limited to: wired or satellite TV signal; Or other radio signal, such as broadcast radio, WiFi and mobile telephone signal.For example broadcast radio can comprise a plurality of frequency band: short-wave frequency band, AM frequency band and FM frequency band.If may need three RX path rather than two, the disclosed single receiver of embodiments of the invention can be configured to from all three radio bandses, receive signals simultaneously.

Can realize the Method and Process of describing in embodiment chapters and sections is code and/or the data that can store in computer-readable recording medium described above.When the code of storing on computer system reads and object computer readable storage medium storing program for executing and/or data, computer system is carried out and to be embodied as data structure and code and to be stored in the Method and Process in computer-readable recording medium.

In addition, can comprise Method and Process described below in hardware module.For example hardware module can include but not limited to other programmable logic device (PLD) of special IC (ASIC) chip, field programmable gate array (FPGA) and known or later exploitation now.When activating hardware module, hardware module is carried out the Method and Process comprising in hardware module.

Only for the object of example and description, present the description above to the embodiment of the present invention.They are not intended as exhaustive or restriction present disclosure.Thereby many modifications and variations will be clear by those skilled in the art.Scope of the present invention is defined by the following claims.

Claims

1. a method, comprising:

Receive a plurality of radio frequencies (RF) signal;

Separated described RF signal is to obtain first group of RF signal and the second group of RF signal in the 2nd RF frequency band in a RF frequency band;

Described first group of RF signal down is converted to first group of Low Medium Frequency (low IF) signal in an IF frequency band simultaneously and described second group of RF signal down is converted to second group low IF signal in the 2nd IF frequency band;

Described first group low IF signal and described second group low IF signal are converted to numeric field; And

Process all low IF signals through conversion simultaneously.

2. method according to claim 1, wherein process all low IF signals through conversion simultaneously and comprise:

Based on IF carrier frequency, select corresponding low IF signal; And

The low IF signal that treatment of selected is selected.

3. method according to claim 1, wherein processes all low IF signals through conversion simultaneously and relates to the digital signal processor (DSP) that comprises a plurality of processing units.

4. method according to claim 1, is wherein greater than the frequency difference between a described IF frequency band and described the 2nd IF frequency band at the frequency difference between a described RF frequency band and described the 2nd RF frequency band.

5. method according to claim 4, wherein the frequency difference between a described RF frequency band and described the 2nd RF frequency band is at least 200MHz.

6. method according to claim 1, wherein said RF signal comprises the satellite-signal from a plurality of GLONASS (Global Navigation Satellite System).

7. method according to claim 6, also comprises that the described satellite-signal based on from described a plurality of GLONASS (Global Navigation Satellite System) generates through the output of the location of combination.

8. method according to claim 6, wherein said a plurality of GLONASS (Global Navigation Satellite System) comprise:

GPS (GPS);

Globalnaya?Navigatsionnaya?Sputnikovaya?Sistema(GLONASS)；

Compass navigational system; And

Galileo positioning system.

9. method according to claim 1, the bandwidth of the RF signal that wherein received surpasses 400MHz.

10. a system, comprising:

Broad-band antenna, is configured to receive a plurality of radio frequencies (RF) signal, and described a plurality of RF signals are included in first group of RF signal and the second group of RF signal in the 2nd RF frequency band in a RF frequency band;

Two bandpass filter (BFP), are configured to select the corresponding RF signal of organizing separately;

Two down converters, for the RF signal of selected group, wherein said down converter is configured to described first group of RF signal down is converted to first group of Low Medium Frequency (low IF) signal in an IF frequency band simultaneously and described second group of RF signal down is converted to second group low IF signal in the 2nd IF frequency band separately;

Analog to digital converter (ADC), is configured to described first group low IF signal and described second group low IF signal to be converted to numeric field; And

Digital signal processor (DSP) is configured to process all low IF signals through conversion simultaneously.

11. systems according to claim 10, wherein said DSP also comprises a plurality of digital BPF, wherein respective digital BPF is configured to select corresponding low IF signal based on IF carrier frequency, and wherein said DSP is also configured to the low IF signal that treatment of selected is selected.

12. systems according to claim 10, wherein said DSP comprises a plurality of processing units.

13. systems according to claim 10, are wherein greater than the frequency difference between a described IF frequency band and described the 2nd IF frequency band at the frequency difference between a described RF frequency band and described the 2nd RF frequency band.

14. systems according to claim 13, wherein the frequency difference between a described RF frequency band and described the 2nd RF frequency band is at least 200MHz.

15. systems according to claim 10, wherein said RF signal comprises the satellite-signal from a plurality of GLONASS (Global Navigation Satellite System).

16. systems according to claim 15, also comprise: output generates mechanism, and the described satellite-signal being configured to based on from described a plurality of GLONASS (Global Navigation Satellite System) generates through the output of the location of combination.

17. systems according to claim 15, wherein said a plurality of GLONASS (Global Navigation Satellite System) comprise:

GPS (GPS);

Globalnaya?Navigatsionnaya?Sputnikovaya?Sistema(GLONASS)；

Compass navigational system; And

Galileo positioning system.

18. systems according to claim 10, the bandwidth of the RF signal that wherein received surpasses 400MHz.